Vertical axis turbine hybrid blades

ABSTRACT

Blade designs for combining elements of drag and lift for vertical axis turbines are presented. Doing so may combine the best features of both types of turbine.

FIELD AND BACKGROUND OF THE INVENTION

The present invention relates to a vertical axis wind turbine, and howto make its blades perform better. Drag and lift blades each have theirown benefits and drawbacks; the possibility of combining them for bettertotal performance is presented. Drag blades operate from the push of thewind; lift blades operate like the wing of an aircraft by inducingcirculation changes.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, withreference to the accompanying drawings, wherein:

FIG. 1 is a diagram of hybrid and tapered blades.

FIG. 2 is a diagram of a hybrid drag and lift design.

FIG. 3 is a diagram of arms to hold the blades.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention shows vertical axis turbine blades that deliversolutions to the problem of providing maximal power and maximal quiet atthe same time. Vertical axis blades are less powerful when working in adrag configuration (being pushed by the wind) and noisier but morepowerful when working in a lift configuration (with an airfoil-typeeffect). Lift configurations also have more trouble starting. Therefore,this application attempts to bridge the gap between the two types ofconfiguration by presenting several solutions that increase power to abasically drag configuration or decrease the noise of a liftconfiguration.

Definitions: The environment of the inventions can be any fluid. Theterm “wind” is often used because it is most common, but the inventionsmentioned are adaptable to any fluid, whether gas or liquid. Foils areas generally known in the aircraft industry. If a non-blade foil shapeis close enough to a blade to affect its performance, it is functionallyadjacent to it. Any reference to such a structure is distinct from foilshapes that may be on the blade.

The principles and operation of a vertical axis turbine according to thepresent invention may be better understood with reference to thedrawings and the accompanying description.

Referring now to the drawings, FIG. 1 illustrates a group of hybrid liftand drag blades. We introduce the device of vertical axis turbineblades, or alternatively any blades, being made, at least partially, ofan outline foil shape. In FIG. 1, the bottom of the picture shows anopen blade with a shape on the edge, ideally the outer edge, that curvesback in the direction of the inner edge. One way to define it is anyoutline blade that passes beyond the imaginary line of a half structure.In another embodiment, any blade with a portion that passes thatimaginary line and also turns toward the inner edge is included (FIG.2).

FIG. 1 also illustrates the use of different blade shapes in verticalaxis turbines, in one embodiment, of the Savonius variety. In oneembodiment, the blade itself tapers in shape, either larger or smallerat the periphery or at the center. The reason is that with a superiorand inferior foil, or even just an inferior one, a shape that is notvertically linear may take more advantage of higher velocities near thefoils. The blade itself may change shape along the vertical distributionby being a regular drag blade in one location and a lift blade inanother location as shown. A transitional area may occur. The objectiveis to take advantage of different velocity patterns in connection withthe foils. In another embodiment, each of the above is claimed inassociation with a foil.

In summary, (1) and (2) are different types of lift type blades, (1)being a complete foil. (3) illustrates how the geometry of (2) involvescrossing the chord midline part way. (4) is an example of a drag type ofblade. (5) shows how they can be combined vertically. In this case, thelower and upper parts are drag, and the middle part of the blade islift. The opposite is also possible. (6) illustrates a tapering shape.The reason for this is that a turbine with a lower or upper foilproduces a distribution of higher velocity air even a little in front ofthe foil shape (8), so that a tapered shape that bulges at the middlecan contact that area of higher velocity. This bulge shape of blade isclaimed for drag and lift varieties, and for association with a foil.For orientation, (7) is the shaft.

FIG. 2 is an example of a blade design with one side curved over onitself that can combine elements of lift and drag in one blade. It isclaimed by itself and in association with an FDD foil. The part (9)functions exactly as drag. The special point about the angle between thepoints 10 and 11 is that the inward turning angle directs wind into thecenter of the blade in drag configuration while functioning to deliversome lift due to the foil like appearance.

FIG. 3: The arms holding the blades in a VAWT can be in a streamlinedcollector shape facing the direction of movement of the turbine, eithersharp (12) or rounded like a cup (13), so that they can help start theturbine. This combines some drag with lift or adds to the drag.

While the invention has been described with respect to a limited numberof embodiments, it will be appreciated that many variations,modifications and other applications of the invention may be made.

SUMMARY OF THE INVENTION

The present invention successfully addresses the shortcomings of thepresently known configurations by providing devices for obtainingsimultaneous drag and lift effects with a vertical axis turbine.

It is now disclosed for the first time a blade (defined as including ablade segment) of a vertical axis turbine, comprising:

a. at least two regions of different shapes in a vertical distributionalong the blade. (Note that this does not refer to a different shape atthe very edge, such as a winglet, which is known art. All thesedescriptions refer to more than minimal changes or purely estheticcurves added to the blade design. The regions of two different shapes asdescribed here include the possibility that there may be an area ofgradual transition from one shape to another.)

In one embodiment, the blade further comprises:

b. a foil shape (not the blade) functionally adjacent to the blade.

According to another embodiment, one region is a predominantly dragshape, and one region is a predominantly lift shape.

According to another embodiment, at least one region is a mixed drag andlift shape.

According to another embodiment, the turbine is in a liquid.

According to another embodiment, the different shape is one of differentdimension of the same shape.

In one embodiment, the blade further comprises:

b. a third vertically distinct region of lift or drag.

According to another embodiment, one of the regions is a partial foilshape.

According to another embodiment, the line from the external edge to theendpoint of the partial foil is in the direction of the internal curveof the blade on one side.

According to another embodiment, the line from the external edge on thesecond side to the endpoint of the partial foil is in the direction ofthe internal curve of the blade.

According to another embodiment, one of the regions is a full foil.

In one embodiment, the blade further comprises:

b. a foil shape (not the blade) functionally adjacent to the blade.

It is now disclosed for the first time a blade (defined as including ablade segment) for a vertical axis turbine, wherein the line from theexternal edge to the endpoint of the partial foil, is in the directionof the internal curve of the blade on at least one side.

According to another embodiment, the turbine is in a liquid.

In one embodiment, the blade further comprises:

a foil shape (not the blade) functionally adjacent to the blade.

It is now disclosed for the first time a blade (defined as including ablade segment) of a vertical axis turbine, comprising:

a. shape that bulges peripherally and/or centrally in a verticaldistribution.

In one embodiment, the blade further comprises:

b. a foil shape (not the blade) functionally adjacent to the blade.

It is now disclosed for the first time an arm holding a vertical axisturbine blade, comprising:

a. a streamlined arm facing the direction of movement of the turbinewith a collector shape on the opposite side.

According to another embodiment, the streamlined arm comes to a point infront.

According to another embodiment, the streamlined arm is rounded infront.

According to another embodiment, the turbine is in a liquid.

1-21. (canceled)
 22. A blade, defined as including a blade segment, of avertical axis turbine, comprising: a. At least two regions of differentshapes in a vertical distribution along the blade.
 23. The blade ofclaim 22, further comprising: b. A foil shape functionally adjacent,defined as in a position to increase the fluid velocity entering theblade, to the blade.
 24. The blade of claim 22, wherein one region is apredominantly drag shape, and one region is a predominantly lift shape.25. The blade of claim 22, wherein at least one region is a mixed dragand lift shape.
 26. The blade of claim 22, wherein the turbine is in aliquid.
 27. The blade of claim 22, wherein the different shape is one ofdifferent dimension of the same shape.
 28. The blade of claim 22,further comprising: b. At least a third vertically distinct region oflift or drag.
 29. The blade of claim 22, wherein one of the regions is apartial foil shape.
 30. The blade of claim 29, wherein the line from theexternal edge to the endpoint of the partial foil is in the direction ofthe internal curve of the blade on one side.
 31. The blade of claim 30,wherein the line from the external edge on the second side to theendpoint of the partial foil is in the direction of the internal curveof the blade.
 32. The blade of claim 22, wherein one of the regions is afull foil.
 33. A blade, defined as including a blade segment, of avertical axis turbine, comprising: a. A. shape that bulges peripherallyand/or centrally in a vertical distribution.
 34. The blade of claim 33,further comprising: b. A foil shape (not the blade) functionallyadjacent to the blade.
 35. An arm holding a vertical axis turbine blade,comprising: a. A streamlined arm facing the direction of movement of theturbine with a collector shape on the opposite side.
 36. The arm ofclaim 35, wherein the streamlined arm comes to a point in front.